Main Urban Regions Research Articles

Changes in Population Exposure to Rainstorm Waterlogging for Different Return Periods in the Xiong’an New Area, China

In the context of global climate change and urban expansion, urban residents are encountering greater rainstorm waterlogging risk. Quantifying population exposure to rainstorms is an important component of rainstorm waterlogging risk assessments. This study utilized a two-dimensional hydrodynamic model to simulate the inundation water depth and inundation area resulting from rainstorms, with return periods of 5, 10, 50, and 100 years, in the Xiong’an New Area, and overlaid the gridded population data in 2017 and in 2035 under SSP2 to assess the change in population exposure. The results show that the average inundation depth and area increase were from 0.11 m and 207.9 km2 to 0.18 m and 667.2 km2 as the rainstorm return period increased from once in 5 years to once in 100 years. The greatest water depths in the main urban areas were mainly located in the low-lying areas along the Daqing River. The total population exposed to rainstorm waterlogging for the 5-, 10-, 50-, and 100-year return periods was 0.31, 0.37, 0.50, and 0.53 million, respectively, in 2017. However, this is projected to rise significantly by 2035 under SSP2, increasing 2–4-fold compared with that in 2017 for the four return periods. Specifically, the projected population exposure is expected to be 0.7, 1.0, 1.8, and 2.0 million, respectively. The longer the return period, the greater the increase in population exposure. The proportion of the population exposed at the 0.05–0.2 m water depth to the total population exposure decreases as the return periods increases, whereas the proportion changes in the opposite direction at the 0.2–0.6 m and >0.6 m depth intervals. Spatially, high-exposure areas are concentrated in densely populated main urban regions in the Xiong’an New Area. In the future, more attention should be paid to densely populated low-lying areas and extreme recurrence rainstorm events for urban flood-risk management to ensure population safety and sustainable urban development.

Extraction and Spatiotemporal Evolution Analysis of Impervious Surface and Surface Runoff in Main Urban Region of Hefei City, China

The biophysical composition index (BCI)-based linear spectral mixture model (LSMM) is used in this study to extract the impervious surface (IS), vegetation, and soil coverage of the main urban region (MUR) of Hefei City over the 2001–2021 period. In addition, the Soil Conservation Service-Curve Number (SCS-CN) model is first applied to simulate the surface runoff (SR) in the MUR of Hefei City over the past 21 years, then assessed for simulation accuracy using typical waterlogging points in the study area. On this basis, the spatiotemporal evolution of IS and SR and their relationships in the MUR of Hefei City are investigated and discussed in this study. The obtained results showed that (1) the root-mean-square error (RMSE), mean absolute error (MAE), and systematic error (SE) values of the BCI index-based LSMM are smaller than those of the LSMM, demonstrating a higher extraction accuracy of urban IS extraction of the BCI index-based LSMM. (2) The IS area of the MUR of Hefei City exhibits an increasing trend from 107.555 km2 in 2001 to 387.660 km2 in 2021. In addition, the change rate and change intensity values indicate an increasing–decreasing–increasing trend. The highest change rate and change intensity values are 24.839 km2/year and 23.094%, respectively, and were observed in the 2001–2005 period. (3) The simulated SR (165–195 mm) in the MUR of Hefei City demonstrates an increasing trend in the 2001–2021 period at a rainfall intensity value of 200 mm/d. In addition, the simulated SR amount in the central area exhibits slight changes, while that in the surrounding areas shows substantial variations. (4) The distribution of IS and SR in the MUR of Hefei City reveals strong directional variations, which are all affected by geographical conditions. The IS coverage and SR show high positive correlation coefficients in different years. (5) The present study provides primary data for effective urban planning, water resources management and regulation, and disaster prevention and mitigation in Hefei City, as well as a scientific reference for future studies on urban IS, SR, and their quantitative relationships in other regions.

Three decades of household food availability according to NOVA - Brazil, 1987-2018.

ABSTRACTOBJECTIVETo evaluate the trend of household food acquisition according to the NOVA classification in Brazil between 1987–1988 and 2017–2018.METHODSWe used household food acquisition data from five editions of the Pesquisas de Orçamentos Familiares (Household Budget Surveys), conducted by the Instituto Brasileiro de Geografia e Estatística (Brazilian Institute of Geography and Statistics), in the years 1987–1988, 1995–1996, 2002–2003, 2008–2009, and 2017–2018. All reported foods were categorized according to the NOVA classification. The household availability of food groups and subgroups was expressed through their share (%) in total calories, for all Brazilian families, by household situation (urban or rural), for each of the five geographic regions of the country, by fifths of the household income per capita distribution (2002–2003, 2008–2009 and 2017–2018 surveys), and for the 11 main urban regions of the country (1987–1988, 1995–1996, 2002–2003, 2008–2009 and 2017–2018 surveys). Linear regression models were used to assess the trend of increasing or decreasing food purchases.RESULTSThe diet of the Brazilian population is still composed predominantly of foods in natura or minimally processed and processed culinary ingredients. However, our findings point to trends of increasing share of ultra-processed foods in the diet. This increase of 0.4 percentage points per year between 2002 and 2009 slowed down to 0.2 percentage points between 2008 and 2018. The consumption of ultra-processed food was higher among households with higher income, in the South and Southeast regions, in urban areas, and in metropolitan regions.CONCLUSIONOur results indicate an increase in the share of ultra-processed foods in the diet of Brazilians. This is a worrisome scenario, since the consumption of such foods is associated with the development of diseases and the loss of nutritional quality of the diet.

Effect of Urbanization on the River Network Structure in Zhengzhou City, China.

Hydrological problems, such as flood disasters, can be caused by the influence of urbanization on river network structures in plain areas. Taking the main urban region of Zhengzhou city as the research area, based on six remote sensing images from 1992 to 2015, the modified normalized difference water index method and a land-use transfer matrix were used to reconstruct river network data to study the temporal and spatial changes in the river system. In addition, the analytic hierarchy process and the entropy weight method were used to construct pattern indexes of the river system to quantitatively evaluate the inner relationship between the urbanization process and the river network structure in the plain area. The results showed that the percentages of arable land, forest and grassland, water, and unused land in Zhengzhou that was transferred to construction land from 1992 to 2015 were 59.10%, 51.05%, 29.83%, and 58.76%, respectively. In the past 34 years, the morphological indices, structural indices, and connectivity indices of the river system experienced a trend of high to low, and then increased, with the structural indices being significantly correlated with construction land use (p < 0.05). The regression equation R2 between urbanization level and river length, water area, river network density, water surface rate, connection rate, and connectivity ranged from 0.677 to 0.966, which could well reflect the response relationship between urbanization and the river network. In addition, the outflow was greater than the inflow, which has destroyed the natural structure of the channel.

Study on Spatial and Temporal Distribution Characteristics of PM2.5 in the Main Urban Area of Nanjing and Influencing Factors

The study used multiple linear regression models and the inverse distance weight interpolation method to construct a regression analysis model of PM2.5 concentration influencing factors based on the measured data of 9 PM2.5 concentration monitoring points in Nanjing from 2012 to 2019, in order to clarify the spatial and temporal distribution characteristics of PM2.5 pollution in the main urban area of Nanjing. The results show that industrial land area, arable land area, and the density of food and beverage outlets all contribute to PM2.5 concentration, while forest land area has a certain inhibitory effect on the increase of PM2.5 concentration; simulation results show that PM2.5 concentration in Nanjing’s main urban area is decreasing year by year, and the spatial distribution of PM2.5 is primarily influenced by the density of food and beverage outlets. The modeling findings reveal that PM2.5 concentrations in Nanjing’s main urban region are decreasing year by year, with a “low north and high south” pattern dominating the spatial distribution.

Pollution Characteristics and Risk Assessments of Mercury in the Soil of the Main Urban Regions in a Typical Chinese Industrial City: Changchun

Pollution Characteristics and Risk Assessments of Mercury in the Soil of the Main Urban Regions in a Typical Chinese Industrial City: Changchun

Knowledge Economy Clustering at the Intrametropolitan Level: Evidence from Madrid

Despite the increasing relevance of knowledge-based activities in the global economy, their spatial distribution at the intrametropolitan scale has rarely been studied. The aim of this paper is to shed light on the intrametropolitan spatial localisation of knowledge-based activities by assessing some of its main causal mechanisms, paying special attention to agglomeration economies and borrowed size (both questioned in the era of Information and Communications Technologies because of the theorised ‘death of distance’), the controversial role of industrial diversity and specialisation (traditionally considered exclusive processes) and path dependence. The empirical application refers to the case of the Madrid urban region for the period between 2012 and 2017. This study area proves particularly appropriate for two main reasons. First, the area is a main urban region in the European and global urban systems. Second, the area is a good example of a multicore urban region with a traditionally strong metropolis. The results show that the knowledge economy remains strongly dependent on the size of the city itself (agglomeration economies) and of the surrounding areas (borrowed size), that the specialisation and diversity processes are complementary and appear at different scales and that in the specialisation of certain areas in some knowledge economy activities, the city’s trajectory (path dependence) plays an important role. The results of the present study have various practical implications for policymakers when considering not only strategies (and investments) to coordinate land availability, worker training, connections between research centres and companies and amenities but also strategies to coordinate with the surrounding municipalities (e.g. in terms of mobility or joint public and private projects).

Mapping Heat-Related Risks in Northern Jiangxi Province of China Based on Two Spatial Assessment Frameworks Approaches.

Heat-health risk is a growing concern in many regions of China due to the more frequent occurrence of extremely hot weather. Spatial indexes based on various heat assessment frameworks can be used for the assessment of heat risks. In this study, we adopted two approaches—Crichton’s risk triangle and heat vulnerability index (HVI) to identify heat-health risks in the Northern Jiangxi Province of China, by using remote sensing and socio-economic data. The Geographical Information System (GIS) overlay and principal component analysis (PCA) were separately used in two frameworks to integrate parameters. The results show that the most densely populated community in the suburbs, instead of city centers, are exposed to the highest heat risk. A comparison of two heat assessment mapping indicates that the distribution of HVI highlights the vulnerability differences between census tracts. In contrast, the heat risk index of Crichton’s risk triangle has a prominent representation for regions with high risks. The stepwise multiple linear regression zero-order correlation coefficient between HVI and outdoor workers is 0.715, highlighting the vulnerability of this particular group. Spearman’s rho nonparametric correlation and the mean test reveals that heat risk index is strongly correlated with HVI in most of the main urban regions in the study area, with a significantly lower value than the latter. The analysis of variance shows that the distribution of HVI exhibits greater variety across urban regions than that of heat risk index. Our research provides new insight into heat risk assessment for further study of heat health risk in developing countries.

Incidence of metabolic syndrome and determinants of its progression in Southern Iran: A 5-year longitudinal follow-up study.

Background:Metabolic syndrome (MetS) is a cluster of conditions increasing the risk of serious diseases. This study aimed to define the predictors of MetS incident in a community-based cohort in Southern Iran, during a mean follow-up period of 5.1 years.Materials and Methods:During the mean follow-up period of 5.1 years, a cohort study was conducted on 819 Iranian adults aged ≥18 years at baseline and followed to determine the incidence and predictors of MetS progression in Shiraz, a main urban region in the southern part of Iran. The International Diabetes Federation Guideline was used to detect the MetS. Multiple Cox's proportional hazards models were also used to estimate the predictors of new-onset MetS.Results:The prevalence of MetS was 25.9% at baseline, and the overall incidence of subsequent MetS was 5.45% (95% confidence interval [CI]: 4.47–6.59). The incidence of MetS was significantly higher in women (7.12% [95% CI: 5.52–9.05]) than in men (3.92% [95% CI: 2.80–5.34]). Moreover, it increased by 5.02 (95% CI, 3.75–6.58) among individuals who had one metabolic component and by 12.65 (95% CI, 9.72–16.18) for those who had three or more components (P < 0001). The incidence of MetS was also analyzed using the multiple Cox's proportional hazards model for potential risk factors, and it was revealed that female gender (hazard ratio [HR] 2.45; 95% CI: 1.33, 4.50; P = 0.004), higher body mass index (HR 3.13; 95% CI: 1.43.6.84; P = 0.012), increased abdominal obesity (HR 1.45; 95% CI 0.85, 2.46; P = 0.045), smoking (HR 4.79; 95% CI 2.09, 10.97; P < 0.001), and lower high-density lipoprotein (HR 0.53; 95% CI: 0.29, 1.00; P = 0.044) significantly predicted the onset of MetS at baseline; however, age, systolic and diastolic blood pressure, serum uric acid, fasting blood glucose, cholesterol, triglyceride and creatinine, estimated glomerular filtration rate, marital status, level of education, and level of physical activity did not independently predict the onset of MetS when other covariates were considered.Conclusion:This study showed the high-incidence rates of MetS in males and females residing in Southern Iran. Therefore, the prevention through community-based lifestyle modification should be implemented to reduce the burden of MetS and its complications.

Study of the natural rainstorm moving regularity method for hyetograph design

Using minute-based precipitation data for the period of 1961–2016 from the National Basic Weather Station of Shapingba, the main urban region of Chongqing, China, and by combining the concept of moving sampling with the natural rainstorm process, a novel sampling technique called natural rainstorm moving sampling was designed. A novel design hyetograph method, the natural rainstorm moving regularity (NRMR) method, was derived from this sampling technique for hyetograph design. The samples obtained through natural rainstorm moving sampling were compared with those obtained from the annual maximum method (a commonly used sampling method) and with actual waterlogging records. Fuzzy identification verified the rationality of the NRMR method in determining the peak shape. In addition, the NRMR method, the Pilgrim and Cordery (PC) method, the Chicago method, and the common-frequency method were compared; the results showed that natural rainstorm moving sampling is a reasonable sampling approach, and it is simpler and more applicable than the other methods. The results of this study provide a scientific basis and reference for urban drainage design to reduce urban waterlogging disasters in Chongqing. At present, the results have been applied in the formulation of the rainstorm intensity and the design of a rainstorm hyetograph in Chongqing.

Long-term spatiotemporal variations of atmospheric sulfur, nitrogen and particle pollutants in Chongqing, southwest China: implication of industrial transfer.

Industrial transfer has swept through in China. However, there is still a knowledge gap about its environmental effects. In this study, industrial transfer status was assessed and evaluated by industrial ratios (%; the gross product contributions of the secondary industry to the whole industry) and the impact of such transfer on atmospheric environment (SO2, NO2, PM10 (particles with aerodynamic diameter less than 10 μm), precipitations of SO42-, NO3-, and NH4+) in the 38 districts and counties in Chongqing was analyzed and discussed for the period of 2006-2015. Results showed that industries were transferred obviously from the main urban region (MUR) into the 1-h economic region (OHER). Atmospheric sulfur and PM10 were efficiently put in control, but atmospheric nitrogen (NO2; precipitations of NO3- and NH4+) was increasing and posted a potential threat to air quality especially during 2011-2015. Correlations showed that industrial ratios had significantly positive relationships with concentrations of ambient SO2 and PM10 in the MUR and ambient NO2 in the OHER (p < 0.05) while a remarkably negative one with concentrations of ambient SO2 in the OHER (p < 0.05) during 2006-2015, implying that industrial transfer could be effective in transferring sulfur pollution but not as efficient in transferring atmospheric nitrogen and PM10 pollutions as SO2 between in the MUR and OHER. More measures should be taken to reduce nitrogen and PM10 emission and a regional monitoring network of ambient NH3 is in urgent need.

Path dependence in net migration during the ICT boom and two other growth periods: the case of Finland, 1980-2013

This paper examines the path dependence of net migration surpluses and deficits by Finnish municipalities in the period of 33 years. Such spatial clustering revealed by spatial autocorrelation represents the spatial formations in which the development indicated by migration is statistically similar over the municipal borders. The results of survival analysis indicate that the chronic centripetal tendency of development generates higher path probabilities of a municipality staying in a surplus formation located in the main urban regions and an increased lock-in tendency compared with deficit formations in peripheries. Thus, the growth processes seem to translate into the self-reinforcing spatial formations of growth and decline in population, production and regional competitiveness suspended by economic downturns and recessions, and so this path dependence is cyclic and recurring, which means that paths constitute relatively short pulses. In the great surge of Information and Communication Technology industries in the 1990s, the spatial formations of migration were higher in volume and path-dependent, but against expectations, spatially less stable compared with more modest growth periods.

Characterizing Spatiotemporal Pattern of Land Use Change and Its Driving Force Based on GIS and Landscape Analysis Techniques in Tianjin during 2000–2015

The spatial and temporal characteristics and driving factors analysis of regional land use are the core scientific problems in the research of ecological environment and human sustainable development. It is also an important basis for the government to formulate land management policy. Based on the land use maps of 2000, 2005, 2010 and 2015, this article analyzed the spatiotemporal pattern of land use change in Tianjin, and determined the relative importance of each driving factor of land use change. The main features of land use change were the continuous expansion of built-up land (1386.89 km2/74.73% gains) and the decrease of arable land area (1181.60 km2/16.84% losses). The area and intensity of land use change were not completely consistent, such as Wuqing and Jixian. The hotspots of land use change mainly were located in the main urban region in Tianjin, around the suburban settlements and Binhai New Area. The landscape pattern in the research region has also changed significantly. The Largest patch index (LPI) and largest shape index (LSI) of arable land showed an increasing trend, and the degree of landscape fragmentation of arable land was deepened. The trend of landscape index of built-up land was similar to that of arable land, but the change intensity was more severe. In addition, the article also used the stepwise regression analysis in the multiple regression to analyze the relative importance of various driving factors, indicating that the driving factors of the built-up land and arable land change were obviously different in different periods. Government policies also have a significant impact on land use change, such as establishing the Tianjin Binhai New Area (TBNA).

The making of the gourmet restaurateur – masculine ideology, identity and performance

ABSTRACTIn recent decades, there has been growing interest in renowned gourmet restaurants, and increased awareness about how food is prepared, presented and served. A small and select group of chefs have thereby gained prestigious positions and high-profile images as restaurateurs. Most of these restaurateurs are men. The research question this article sets out to study is: How is the identity and ideology of masculinity imbued into the subjectivity and representations of gourmet restaurateurs? The selection of data sources means that our geographical focus is on Stockholm, Sweden’s main urban region. The methodological approach of this article to employ empirical material from interviews and media articles reveals how this masculine discourse is attained through a particular interplay of subjects (the chefs and entrepreneurs) and representations (the media). The focus of this article has included a quite exclusive category of a few restaurants and restaurateurs, which may have implications on the findings pointing to a homogenous profile of the ideals of the gourmet chefs. The results point out that the micro-spaces of gourmet restaurants’ kitchens and dining rooms can be understood as nurseries for ‘nostalgic and conservative masculinities’.

Incentives and Disincentives to City-Regional Cooperation in the Berlin-Brandenburg Conurbation

Current academic discussions on economic development make a case for `regional governance' in city-regions and stress the importance of varying institutional and policy-making frameworks for country-specific interpretations of `regionalization'. This article will look at the evolution of forms and structures of regional governance in two of the main urban regions in western Europe, London and Berlin. They have been chosen for their underlying structural-geographic comparability, including their international outlook and awareness of competitiveness, while at the same time representing quite different constitutional and institutional arrangements for territorial governance in general, and that for city regions in particular. Nevertheless, as shown in this article, there appears to be the common challenge of an institutional lag in the adjustment of city-regional government to the imperatives of regional economic competition. This may even go as far as institutional arrangements not only being ineffective but obstructive to the development of city-regional governance through in-built support of localist or institutionalist ambitions. Drawing new boundaries between territories of institutional responsibilities, establishing institutional `performance targets' or fiscally rewarding inter-local competition, are just some of the obstacles to building effective city regional governance.

Regional R&D activities and interactions in the Swedish Triple Helix

The Swedish innovation system is analysed in terms of the interaction between academia, government and the private sector. For each of 21 Swedish regions we analyse the distribution of research activities, doctoral employment, and publication output, as well as the flow of doctoral graduates and the distribution of co-authorship links across regions and sectors. The three main urban regions have about 75 percent of all R&D activities and outputs. They also have a more balanced supply of academic, governmental and private research activities than the smaller regions, and the interactions among sectors within these regions are more intense. The inter-regional flow of PhDs is also to the advantage of the big regions. So far, decentralization of the academic sector does not seem to have had as similar decentralizing effect on private R&D. Unless this imbalance changes, smaller regions will continue to be net exporters of skill and knowledge to the big regions.

Prospective study on physical planning and the environment in the megalopolis in formation in North-West Europe

In December 1972 the Commission of the European Communities requested the European Research Institute for Regional and Urban Planning (ERIPLAN) in The Hague, to undertake, in collaboration with other national or regional research institutes, a prospective study on physical planning and the environment in the megalopolis in formation in North-West Europe. The extensive study was submitted to the Commission in April 1974. A synthesis report has been prepared for publication and was submitted to the Commission in March 1975. In North-West Europe the process of urbanization is developing across the national borders of five countries, giving rise to an urban concentration in which 80 million people live and work. The study area covers a surface of 230,000 km 2, its average population density being more than 350 people/km 2. A “core area” of the megalopolitan regions has been defined which contains 73% of the total population, 70% of all industrial employment and almost half of all agricultural employment of the study area. The methodological framework of the study is based on the dependence of urban regions upon open spaces. The typology of open spaces in North-West Europe shows two large complexes, called megalopolitan open spaces, north and south of the continental megalopolis, which are of very divergent nature and possess high potentials for balancing the exogenous demands of the megalopolitan central core. Further, three inter-metropolitan open spaces and a series of metropolitan open spaces have been identified. Their evaluation includes their productive, ecological and social functions. The study of open spaces allowed particularly to enlighten their supra-national dimensions and their importance for recreation and ecological regulation considered from a supra-national point of view. The dynamics of urbanization are investigated on several levels: regional concentration and dispersal tendencies of population based on trend analysis and available projections, regional consumption of space through urbanisation and metropolitan expansion. The five main urban regions: Central South-East England, Randstad Holland, Rhine-Ruhr conurbation, Franco-Belgian conurbation and Paris, account for 46% of the total population in the study area. Areas with a high population growth and particularly of migration surplus exhibit typical locations: some of them are within inter-metropolitan buffer zones, others are immediately adjacent to the largest metropolitan areas. The pattern of concentration of population and activities, however, favours the coastal regions and those situated along the main rivers and estuaries. The deconcentration of the residential function in metropolitan areas causes an increasing volume of commuting movements over growing distances, and therefore further consumption of material and human energy. The related process of suburbanization around the metropolitan areas, strengthened by growing per capita space needs, leads to the accelerated and irreversible conversion of open space into urban land. Population growth is apparently not the major assaillant of open spaces: during the past decade, in fact, urban land increased at a rate that was on average rather more than double that of population growth. Wide disparities, however, become apparent among national land use patterns. The trends analysed in the urbanization and pollution processes, when confronted with the evaluation of open spaces, reveal the intensity of pressure which is exerted on them, and therefore the reduction of the regulation capacity. Urbanization pressure on the Belgo-Dutch-German intermetropolitan open space is particularly high. More generally, water pollution and water supply appear to be a major problem of the North-West European regions. Underground supplies are increasingly polluted and have already reached their limit of exploitation, while filtering of river water is becoming increasingly difficult because of the growing concentration of toxic products and heavy metals. The response of policies outlined in official documents to the problems identified in this report shows how these problems are likely to be tackled and also illustrates the degree of awareness about supra-national and transfrontier evolutions. Further, identified trends, when compared to the objectives proposed by the official policies, reveal the degree of success achieved in the implementation of these objectives. The emergence of conflict in such confrontations lead to new proposals for action, building the framework of a hypothetical, but highly desirable megalopolitan planning. The further investigation of the identified problems through more detailed and precise studies appear, however, necessary.